pub fn nth(n: u32) -> u32 {
    fn is_prime(num: u32) -> bool {
        !(2..num).into_iter().any(|v| num % v == 0)
    }
    let mut count = 0;
    let mut prime_base = 2;
    while count != n {
        prime_base += 1;
        if is_prime(prime_base) {
            count += 1
        }
    }
    prime_base
}

#[test]
#[ignore]
fn big_prime() {
    assert_eq!(nth(10_000), 104_743);
}